Master Install Kit Contents
What's in a 'master kit': pinion bearings, carrier bearings, races, crush sleeve, seals, shims, marking compound, hardware. Buy a master — don't piecemeal.
A 'master install kit' includes everything needed to set up a new ring and pinion. Contents typically:
Bearings:
- Pinion inner bearing
- Pinion outer bearing
- Carrier bearings (left and right)
Races (cups for the bearings):
- All matching the bearings above
Seals:
- Pinion seal
- Axle shaft seals (sometimes)
- Carrier breather (sometimes)
Preload control:
- Crush sleeve (most factory designs)
- OR solid pinion spacer (better, requires shimming setup but doesn't crush — reusable in subsequent rebuilds)
Shims:
- Pinion depth shims
- Carrier preload shims
Hardware:
- Pinion nut
- Ring gear bolts (if needed)
- Carrier bolts
Setup tools (sometimes):
- Marking compound (yellow Permatex or equivalent)
- Loctite for ring gear bolts
- Sometimes a fluid charge
Do NOT buy gears without a master kit. Cheap kits skip bearings or include used races, which always cost more in problems than the kit saves.
Buying piecemeal is also possible — pinion bearings from Timken, carrier bearings from KOYO, seals from National. Adds up to about the same money but introduces brand mismatching.
For a Dana 30 install: Yukon YK D30, Motive MK D30, USA Standard ZK D30. All include the same essential contents; brands vary slightly.
Upgrade option: solid pinion spacer kits (Yukon, Nitro). Replaces crush sleeve. Requires shimming for preload but is reusable and more accurate. $25-50 add-on. Worth it for any rebuilder who plans to set up gears repeatedly.
Why it works
- all parts matched
- convenient
- reliable setup
Trade-offs
- nothing
Tools required
- dial indicator
- bearing splitter
Parts
| Part | Vendor | Est. price |
|---|---|---|
| Yukon master install kit (any axle) | Yukon | ~$250 |
| Yukon solid pinion spacer upgrade | Yukon | ~$40 |
Sources
Related
- Slip Yoke Eliminator (SYE) — Hack-N-Tap vs Full Kit
- AW4 Governor / Shift Kit
- All Jeep Cherokee XJ guides & tools
- Browse the full DIY database
Written and maintained by an AZ wheeler and driveway wrencher. How we source guides. Always cross-reference your factory service manual — modifications affect vehicle safety and warranty. Work at your own risk.